11/19/2017
"Oh no, my Check Wallet light is on!"
Few people understand what the 'Check Engine" is or how it works.
Back in the late 1900s, as more and more electronics were added to cars, each manufacturer had it's own connector to access the systems, which meant you could only get your car fixed at a dealership. In 1996 the government mandated a standard plug so any repair shop could access the information needed to fix the car - the OBD connector ( On Board Diagnostic) . While the engine is running, control units in your car monitor many of the systems such as ignition, fuel, emissions, transmission and brakes. If there is a malfunction, or something excedes an acceptable value, a message is stored in the memory and the "Check Engine" light is turned on to let you know there is a message/code to be read. It does not mean something is wrong at that very moment, just that there is a code to be read. The code(s) tells the tech what happened (but not why) to assist with the diagnosis. After reading the codes, the tech will clear them which turns the light off. He then road tests the car to see if any of the codes return right away, which would indicate a chronic problem as opposed to a one time occurrence.
Quite often people bring their cars in for the state inspection and the Check Engine light is on. We start by checking the codes to determine if there is a problem and then clearing them to turn off the light. Next, the car has to be driven so the OBD system can monitor the function of 7 critical systems to be sure everything is working as it should. How long does this take? It takes as long as it takes! Usually 15 - 50 miles . There is NO exact distance or time, it's totally up to the computers . The car will not pass the inspection until at least 6 of the 7 monitors are ready and the Check Engine light has not come back on during the reset. While performing the inspection, we have to connect the DMV computer directly to the cars OBD connector. If your cars computer doesn't tell the DMV computer everything is ok, you don't get a sticker !
So, if your Check Engine light is on and your car is coming up for state inspection, bring it in early enough so any problems can be taken care of and the monitors have time to reset before your old sticker expires